This invention relates to a picture processing system for use in a facsimile device in processing an input picture data signal representative of an original picture, such as a natural picture, into a processed picture data signal and, more particularly, to the picture processing system for processing a color natural picture into a binary picture data signal which is for use as the processed picture data signal.
On transmitting a color natural picture representative of a natural sight image, a person image, or the like as an original picture in a facsimile device, the color natural picture is generally inputted into the facsimile device as an input picture data signal as it is. Alternatively, coped picture given by copying the color natural picture, is inputted into the facsimile device as the input picture data signal. The input picture data signal is transmitted by the facsimile device with the input picture data signal converted into a binary picture data signal as a facsimile data signal.
As a further alternative, the input picture data signal is compressed into a compressed picture data signal by a compressing unit included in the facsimile device. The facsimile device further comprises an expanding unit which expands the compressed picture data signal into an expanded picture data signal which approximate to the input picture data signal. That is, the expanded picture data signal represents an approximate picture which approximates to the original picture. A converting unit converts the expanded pictures data signal into a binary picture data signal. A transmitting unit transmits the binary picture data signal as the facsimile data signal to a counterpart facsimile device which has similar functions.
In any one of the above-mentioned facsimile transmission methods,the natural picture can not be reproduced with a high quality by the counterpart facsimile device. This is because any one of the original picture, the coped picture of the original picture, and the approximate picture of the original picture is compelled to be converted into the binary picture data signal.
When any one of the original picture, the copied picture, and the approximate picture is converted into the binary picture data signal and when the binary picture data signal is transmitted as the facsimile data signal, the facsimile data signal inevitably represents an unnatural picture in which stereoscopical feeling or sense disappears. The counterpart facsimile device can not reproduce the original picture with ah high quality from the facsimile data signal in view of fine gradation of a natural color, hue, brightness, and saturation.